The invention relates generally to reinforcement of sliding closures, and more particularly concerns structural reinforcement of patio doors and the like, against structural failure caused by wind pressure oriented in a direction perpendicular to a sliding track of the door.
Sliding doors are commonly used in residential dwellings, apartment units, etc., in a range of types. Such doors may have one movable panel or more. The panel(s) may abut or may lap one another. One of the panels may be fixed and immovable and another may be slidable in a track. The fixed panel and the movable panels may have the same appearance, such as two framed glass panels, or May have a different appearance. Some sliding panels are received in a wall xe2x80x9cpocketxe2x80x9d at least in one of their possible positions.
In a common structural arrangement known as a patio door, one, two or more framed glass panels are provided in a framed opening, typically leading outdoors to a concrete patio if on the ground level or to a deck if on an upper level. Typically, two (or more) panels are movable and lap one another when the door is open. The panels are typically identical framed glass panels, slidable in parallel adjacent tracks in an upper header and in a lower sill. However, it is also possible that two panels may butt against one another and move in the same track. Another possibility is a door having a stationary glass panel and a movable sliding panel that can lap the stationary one when the door is open.
A feature common to the sliding panels in all the foregoing possible door types is that the structures that engage and hold the movable panel in the doorway are the same structures that permit the movable panel to slide back and forth to open and close the door.
For an exemplary glass patio door, one or more relatively large glass panes (e.g., 80 inches high by 36 inches wide, or approx. 200 cm high by 100 cm wide) are mounted in a surrounding metal or wooden frame having parallel tracks in which the edges of the panels fit and are adapted for horizontal sliding movement. The weight of the panel most often is carried on a lower track or rail. The lower track or rail can be channel shaped to receive wheels or tenons or the like that extend from the bottom edge of the door panel, or the track can have a rail or ridge or the like that fits into a channel along the lower edge of the door panel.
Instead of resting by gravity on the lower track or rail, a sliding panel also can be hung by a sliding or rolling mechanism from an upper track. Whether the mounting is from the top rail or the bottom one, the panels frequently require the capability of vertical displacement so that the panel can be installed in its sliding track and if necessary removed. For this purpose, the upper rail may have sufficient vertical clearance that the panel can be displaced upwards from its operative position into the upper rail, for lifting the panel structures over their mating structures in the lower rail and permitting the panel to be placed in the doorway opening or removed. A similar vertical displacement may be needed in doors hung from an upper header rail, to allow a panel to be lifted to disengage the mechanism on which the panel hangs and slides.
An exterior panel may be constructed without this vertical displacement capability because as a security measure it could be ill advised to have an exterior door panel that is very easy to defeat. Nevertheless, whether or not the panels are removable, it is an aspect of sliding doors that the advantage of sliding capability comes with the disadvantage that there is only limited structural connection between the movable panel and the upper header track and/or lower sill track. There may be no load bearing connection other than the fact that the upper and lower edges of the panel and/or track comprise channels having a given depth, with the sidewalls of the channel confining the panel. In some instances the only resistance to a load applied in a direction perpendicular to the plane of the panel is that there are rollers or wheels on one side that roll in a shallow track or groove on the other side. This mechanical structure cannot withstand a great deal of force in a direction perpendicular to the plane of the panel.
In the usual patio door arrangement, a vertical stile along one side edge of the sliding door carries a lock assembly to prevent the panel from sliding away from the jamb when locked, namely in the plane of the panel. A horizontal bottom rail normally includes a roller assembly that is arranged for sliding or rolling engagement with a lower track or rail located in the sill of the door (or vice versa). The lock assembly normally includes a hook-shaped mortise latch for engaging a mating latch keeper mounted on the adjacent door jamb to lock the door against movement to an open position. The roller assembly is normally constructed to provide easy, back-and-forth, horizontal sliding movement of the door. It is inconsistent with the objective of an easily opened door to provide any substantial structural support or a structural tie between the sliding door panel and its fixed framework.
Thus, some prior art sliding doors have been constructed to include a structural connection with the surrounding frame, and with a mid-overlapping edge. These doors often include deep channel structures that are securely attached to the wall of the building so that the door(s) are securely engaged around their peripheral edges. This solution is much more costly to implement, cannot normally be accomplished in a retrofit of an existing door, and still does not address a significant weak point in their design, i.e., the mid-overlapping edges, where the door panels are spaced from the wall of the building. This disadvantage renders such doors especially vulnerable to large forces applied to the door, in a direction perpendicular to the plane of the door. This vulnerability is due to the rolling engagement of the edges of the panels on the sill. The lack of any type of rigid connection or general support at the mid-overlapping edges of the doors often leads to failure under heavy wind loading.
As a result, pressure that is applied to the door, from a direction other than the sliding direction of the door, may be only weakly opposed by the door structure. This condition can lead to catastrophic failure of the door in high wind conditions, e.g., during a hurricane, tornado or other severe weather condition. In this failure mode, the engagement between the rollers and the track may be insufficient to withstand the substantial inward wind pressure and/or outward suction on the door, or the associated vibration of a gusting wind. In this case, the rollers may be dislodged from their engagement with the track, jamming the door or in a severe case disengaging the movable panel entirely from its sliding frame. This can lead to collateral damage to the building or could require costly repair procedures including disassembly or even total replacement of the sliding doors.
As a measure against breaking and entering more than against wind pressure, it is known to employ latch bar mechanisms in cooperation with sliding glass-type doors. These locking or fastening devices may secure the sliding glass units to adjoining frame members to keep them closed, for example a spacer bar can be inserted into the track between a movable panel and the vertical frame or stile member toward which the panel would slide in opening the door. In that case, the structure of the stile also supports the sliding panel, and the sill or bottom rail may have a channel that encompasses the vertical side edge of the movable panel.
As another possibility, a security mechanism can be structured to lock together or to secure together two sliding glass panel units. In an unlocked state the panels are unattached and are capable of sliding relative to each other and relative to the frame in which they are mounted. A bar or rod positioned in a door channel between the door panel and the vertical frame will prevent opening of the sliding door as discussed above. Similarly, by sliding two movable panels in adjacent tracks against opposite vertical frame members of the doorway and then attaching the panels together where they overlap, neither panel can slide back out of abutment with its respective vertical frame member and the panel is locked. However, this effectively doubles the area of the panel subjected to any wind force, without substantially improving the structural engagement of the panels in their tracks. Such devices may be useful to prevent burglaries begun by forcing movable panels open in their tracks, but are less then completely effective in structurally supporting the door panels against displacement or detachment from their tracks.
The present invention provides a support brace, referred to as a storm rail, for structurally linking a sliding door to a surrounding structure, and which may be retrofitted to an already installed sliding door structure. In one embodiment the support brace includes an elongated rail having a first end and a second end, with the rail being abutted against and preferably fastened to a portion of the sliding door in spaced relation to the surrounding structure so that the first end is positioned adjacent to a top edge of the sliding door and the second end is positioned adjacent to a bottom edge of the sliding door. At least one bolt is slidingly secured to the rail, and includes a locking rod. The bolt is arranged so that it can be slid along the rail between a first position wherein the locking rod projects beyond one of the first and second ends of the rail, and a second position wherein one of the first and second ends of the rail projects beyond the locking rod. At least one lock plate is also provided that includes an opening defined through a portion of the plate. The opening is arranged in aligned relation to the locking rod so that when the bolt is slid from the second position to the first position, the locking rod is received in the opening.
In an alternative embodiment of the invention, a support brace for structurally linking a sliding door to a surrounding structure is provided having two rails. Each rail has a first end and a second end, and is fastened to a portion of the sliding door in spaced relation to the surrounding structure so that the first end of one of the rails is positioned adjacent to a top edge of the sliding door and a first end of the other of the rails is positioned adjacent to a bottom edge of the sliding door. At least one bolt is slidingly secured to each of the rails. The bolts each include a locking rod wherein the bolt can be slid along the rail between a first position wherein the locking rod projects beyond one of the first end of the rail, and a second position wherein one of the first end of the rail projects beyond the locking rod. Two lock plates are also provided, each including an opening defined through a portion of the plate. Each of the openings is arranged in aligned relation to one of the locking rods so that when the bolt is slid from the second position to the first position, the locking rod is received in the opening.
A storm resistant sliding door assembly is also provided that includes two sliding doors each including a pair of spaced-apart vertical stiles, a horizontal top rail, a horizontal bottom rail, a roller assembly, and a centrally positioned pane of glass. An elongate rail, having a first end and a second end, is fastened to a vertical stile of one of the sliding doors so that the first end is positioned adjacent to the horizontal top rail of the sliding door and the second end is positioned adjacent to the horizontal bottom rail of the sliding door. At least one bolt is slidingly secured to the rail, and includes a locking rod wherein the bolt can be slid along the rail between a first position wherein the locking rod projects beyond the horizontal bottom rail of the sliding door, and a second position wherein the locking rod is spaced from the horizontal bottom rail. At least one lock plate is also provided that includes an opening defined through a portion of the plate. The opening is arranged in aligned relation to the locking rod so that when the bolt is slid from the second position to the first position, the locking rod is received in the opening.